Perhaps you should try some spelling variations:
sach thien » sach thieu, sach tien, cach thien
thien bang » khien bang, thien ban, thien dang
cau treo » cau theo, cau tren, cau triet
dua tren » dung tren
va kinh » va tinh, qua kinh
so sach » so sanh, bo sach, co sach
va dinh » van dinh, va tinh, vu dinh
hieu va » lieu va, hieu qua
bang xa » lang xa, bang va, mang xa
va cau » van cau, va cac, va dau

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: so sach thien bang xa hoi. hieu va cau truc ((va dinh) or (va kinh)) vi ((dua tren) or (cau treo))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: so sach thien bang xa hoi. hieu va cau truc ((va dinh) OR (va kinh)) vi ((dua tren) OR (cau treo)).
• Adding a wildcard symbol may retrieve word variants: so sach thien bang xa hoi. hieu va cau truc ((va dinh) or (va kinh)) vi ((dua tren) or (cau treo))*.